JP2023180700A - Organic compound and organic light-emitting element - Google Patents

Abstract

To provide an organic compound excellent in light emission efficiency and durability characteristics.SOLUTION: The organic compound is represented by general formula [1] in the figure. In the formula, R1 to R10 are each independently selected from the group consisting of a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group. However, at least one of R2, R3, R8 and R9 is selected from the group consisting of a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group.SELECTED DRAWING: None

Description

The present invention relates to organic compounds and organic light emitting devices.

An organic light emitting device (hereinafter sometimes referred to as an "organic electroluminescent device" or "organic EL device") is an electronic device that has a pair of electrodes and an organic compound layer disposed between these electrodes. By injecting electrons and holes from these pair of electrodes, excitons of the luminescent organic compound in the organic compound layer are generated, and when the excitons return to the ground state, the organic light emitting device emits light. . Recent advances in organic light-emitting devices have been remarkable, including low driving voltages, various emission wavelengths, high-speed response, and the ability to make light-emitting devices thinner and lighter.
By the way, the creation of compounds suitable for organic light emitting devices has been actively carried out to date. This is because, in providing a high-performance organic light-emitting device, it is important to create a compound with excellent device lifetime characteristics. As a compound created so far, chromeno[2,3-a]xanthene-8,14-dione (CXD) is described in Patent Document 1.

US Patent Application Publication No. 2020/44159

Although Patent Document 1 discloses the use of CXD as a host in a light emitting layer of an organic light emitting device, further improvements in luminous efficiency and durability characteristics are desired.
The present invention has been made in view of the above-mentioned problems, and its purpose is to provide an organic compound and an organic light-emitting element that have excellent luminous efficiency and durability characteristics.

The organic compound of the present invention is characterized by being represented by the following general formula [1].

一般式［１］において、Ｒ₁乃至Ｒ₁₀は、水素原子、重水素原子、置換あるいは無置換のアルキル基、置換あるいは無置換のアリール基、置換あるいは無置換の複素環基からそれぞれ独立に選ばれる。ただし、Ｒ₂、Ｒ₃、Ｒ₈、Ｒ₉のうちの少なくとも一つは、重水素原子、置換あるいは無置換のアルキル基、置換あるいは無置換のアリール基、置換あるいは無置換の複素環基から選ばれる。

In the general formula [1], R ₁ to R ₁₀ are each independently selected from a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group. It will be done. However, at least one of R ₂ , R ₃ , R ₈ , and R ₉ is a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group. To be elected.

According to the present invention, it is possible to provide an organic compound with excellent luminous efficiency and durability. Moreover, by using the organic compound of the present invention as a host molecule of a light emitting layer, it is possible to provide an organic light emitting device with excellent luminous efficiency and durability.

(a) It is a schematic cross-sectional view showing an example of a pixel of a display device concerning one embodiment of the present invention. (b) A schematic cross-sectional view of an example of a display device using an organic light emitting device according to an embodiment of the present invention. FIG. 1 is a schematic diagram showing an example of a display device according to an embodiment of the present invention. (a) It is a schematic diagram showing an example of an imaging device concerning one embodiment of the present invention. (b) It is a schematic diagram showing an example of the electronic device concerning one embodiment of the present invention. (a) It is a schematic diagram showing an example of a display device concerning one embodiment of the present invention. (b) It is a schematic diagram showing an example of a foldable display device. (a) It is a schematic diagram showing an example of the lighting device concerning one embodiment of the present invention. (b) is a schematic diagram showing an example of a moving object having a vehicle lamp according to an embodiment of the present invention. (a) It is a schematic diagram showing an example of a wearable device concerning one embodiment of the present invention. (b) It is a schematic diagram showing another example of the wearable device concerning one embodiment of the present invention. (a) FIG. 1 is a schematic diagram showing an example of an image forming apparatus according to an embodiment of the present invention. (b) is a schematic diagram showing an example of an exposure light source of an image forming apparatus according to an embodiment of the present invention.

≪Organic compounds≫
The organic compound of this embodiment is represented by the following general formula [1].

<R ₁ to R ₁₀ >
In the general formula [1], R ₁ to R ₁₀ are each independently selected from a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group. It will be done. However, at least one of R ₂ , R ₃ , R ₈ , and R ₉ is a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group. To be elected.

At least one or two, preferably two, of R ₂ , R ₃ , R ₈ , and R ₉ are substituted or unsubstituted alkyl groups, substituted or unsubstituted aryl groups, or substituted or unsubstituted heterocycles. It is preferably selected from groups, and more preferably selected from substituted or unsubstituted aryl groups and substituted or unsubstituted heterocyclic groups. Furthermore, at least one of R ₂ and R ₃ and at least one of R ₈ and R ₉ are a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic ring. It is preferably selected from groups, and more preferably selected from substituted or unsubstituted aryl groups and substituted or unsubstituted heterocyclic groups. Most preferably, R ₂ and R ₈ are preferably selected from a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, and a substituted or unsubstituted aryl group, It is more preferably selected from substituted or unsubstituted heterocyclic groups.

Examples of the alkyl group include a methyl group, an ethyl group, a normal propyl group, an isopropyl group, a normal butyl group, a tertiary butyl group, an isobutyl group, a secondary butyl group, an octyl group, a dodecyl group, a cyclohexyl group, a 1-adamantyl group, Examples include, but are not limited to, 2-adamantyl group. Among these, methyl group and tert-butyl group are preferred.

Examples of the aryl group include phenyl group, naphthyl group, indenyl group, biphenyl group, terphenyl group, fluorenyl group, anthracenyl group, phenanthryl group, fluoranthenyl group, pyrenyl group, chrysenyl group, triphenylenyl group, perylenyl group, etc. These include, but are not limited to. Among these, phenyl, biphenyl, terphenyl, fluorenyl, and phenanthryl groups are preferred.

Examples of the heterocyclic group include pyridyl group, pyrimidyl group, pyrazyl group, triazyl group, triazolyl group, oxazolyl group, oxadiazolyl group, thiazolyl group, thiadiazolyl group, quinolyl group, acridinyl group, phenanthrolyl group, dibenzofuranyl group, and dibenzolyl group. Examples include, but are not limited to, thienyl groups. Among these, pyridyl, pyrimidyl, pyrazyl, triazyl, phenanthrolyl, dibenzofuranyl, and dibenzothienyl groups are preferred. The heterocyclic group is preferably a heteroaryl group, and preferably a group bonded through carbon atoms.

Examples of substituents that the alkyl group, aryl group, and heterocyclic group may further include: deuterium atom; methyl group, ethyl group, normal propyl group, isopropyl group, normal butyl group, tertiary butyl group, secondary butyl Alkyl groups such as octyl group, cyclohexyl group, 1-adamantyl group, 2-adamantyl group: phenyl group, naphthyl group, indenyl group, biphenyl group, terphenyl group, fluorenyl group, phenanthryl group, fluoranthenyl group, triphenylenyl group Aryl groups such as pyridyl group, pyrimidyl group, pyrazyl group, triazyl group, triazolyl group, oxazolyl group, oxadiazolyl group, thiazolyl group, thiadiazolyl group, acridinyl group, phenanthrolyl group, dibenzofuranyl group, dibenzothienyl group, etc. Examples include, but are not limited to, cyclic groups and cyano groups.

The organic compound of this embodiment has a structure in which a specific group other than a hydrogen atom is introduced into a specific position in the CXD skeleton. By doing so, the chemical stability is improved compared to CXD, and when used as a host molecule in the light emitting layer of an organic light emitting device, excellent durability characteristics can be achieved. The mechanism of its action and effect will be described in detail below.

Hydrocarbon or heterocyclic fused polycyclic compounds have a high electron density on the ring plane and are highly chemically reactive. It is known that it has particularly high reactivity toward electrophilic substitution reactions and reacts with electrophilic chemical species in an electron-deficient state. In the light-emitting layer of an organic light-emitting device, host molecules in a radical cation state exist as hole carriers. Molecules in this one-electron oxidation state behave as electrophilic species and can react with other host molecules. Therefore, the stability of the compound in the oxidation state was evaluated by cyclic voltammetry (CV). In CXD, new peaks were observed by repeatedly performing insertion on the oxidation side. This is considered to be because electrophilic chemical species such as radical cations generated by the oxidation of CXD cause chemical reactions such as electrophilic substitution reactions to generate new molecules. On the other hand, exemplified compounds A-1 and A-40 in _which groups other than hydrogen atoms have been introduced into R ₂ and _{R 8 of} general formula [1], In the exemplified compounds C-1 and C-19 into which a group has been introduced, no new peak was observed due to repeated insertion. The results are summarized in Table 1.

Cyclic voltammetry (CV) was performed in an acetonitrile solution of 0.1 M tetrabutylammonium perchlorate, using Ag/Ag ⁺ as a reference electrode, Pt as a counter electrode, and glassy carbon as a working electrode. Further, the insertion speed during repeated insertion was 1.0 V/s. The measuring device used was Model 660C, an electrochemical analyzer manufactured by ALS.

By introducing a group other than a hydrogen atom into a specific position of the CXD skeleton in this way, stability in an oxidized state was improved. The factors for this are estimated as follows. The CXD skeleton has a phenolic oxygen atom, and the electron density on the para position, that is, the carbon to which R ₂ and R ₈ in general formula [1] are bonded (referred to as C2 and C10, respectively) is particularly high. Therefore, it can be said that C2 and C10 are in a state where they are likely to form a bond when attacked by an electrophilic species. In the case of CXD, since only hydrogen atoms are bonded to the carbon atoms adjacent to C2 and C10, respectively, electrophilic species can attack C2 and C10 without any steric hindrance. On the other hand, in compounds in which groups other than hydrogen atoms are introduced into R ₂ and R ₈ of general formula [1], and in compounds in which groups other than hydrogen atoms are introduced into R ₃ and R ₉ of general formula [1], , attack on C2 and C10 by electrophilic species is reduced due to steric hindrance of groups other than hydrogen atoms. As a result, it can be said that the compound of this embodiment was stable without causing any chemical reaction in the oxidized state.

Here, it is known that the electron density is high not only at the para position of the phenolic oxygen atom but also at the ortho position. However, due to the steric hindrance of the phenolic oxygen atom itself, the ortho carbon atom is less susceptible to attack by larger electrophilic species. In fact, from the results in Table 1, in compounds with a CXD skeleton, no new peaks are observed in CV even if groups other than hydrogen atoms are introduced at the ortho position (Example Compounds A-1, A-40, C-1, C-19). Therefore, from the viewpoint of decomposition by electrophilic species, it is highly effective and preferable to introduce a group other than a hydrogen atom to at least the para position (C2, C10) or the carbon atom adjacent to C2, C10.

Examples of the carbon atom adjacent to C2 and C10 include the carbon atom to which R ₃ and R ₉ in general formula [1] are bonded, and the carbon atom to which R ₁ and R ₇ are bonded (referred to as C1 and C9, respectively). When a group other than a hydrogen atom is introduced into C1 or C9, steric repulsion occurs with the oxygen atom of the carbonyl group, causing distortion in the entire molecule and possibly lowering the binding energy of the molecule. In this case, when high excitation energy is applied in the light-emitting layer of the organic light-emitting device, there is a risk that the molecules will decompose due to bond cleavage, resulting in decreased durability. Therefore, from the viewpoint of durability, it is preferable to introduce a group other than a hydrogen atom into the carbon atom to which R ₃ and R ₉ are bonded.

It is preferable that a group other than a hydrogen atom introduced into at least one of R ₂ , R ₃ , R ₈ , and R ₉ be bonded to the CXD skeleton through a carbon-carbon bond with high binding energy. Examples of such groups other than hydrogen atoms include substituted or unsubstituted alkyl groups, substituted or unsubstituted aryl groups, and substituted or unsubstituted heterocyclic groups. In this carbon-carbon bond, since the carbon atom in the CXD skeleton is an sp ² hybrid orbital, the bond energy is higher when the carbon atom of a group other than a hydrogen atom is an sp ² hybrid orbital than when it is an sp ³ hybrid orbital. It is more preferable because it is higher. Examples of such groups other than hydrogen atoms include substituted or unsubstituted aryl groups and substituted or unsubstituted heterocyclic groups.

From the above, the organic compound of this embodiment is chemically more stable than CXD in an oxidized state, and has improved durability when used as a host molecule in a light emitting layer of an organic light emitting device. Furthermore, it has been found that not only the durability of the organic light emitting device but also the luminous efficiency is improved. Although the detailed mechanism is not clear, it is presumed that introducing groups other than hydrogen atoms reduces excessive aggregation and stacking of the CXD skeleton, making it difficult to generate exciton deactivation sites.

Below, specific structural formulas of the organic compounds of this embodiment are illustrated. However, the present invention is not limited to these.

Compounds belonging to Group A are compounds in which R ₂ and R ₈ are an alkyl group, an aryl group, or a heterocyclic group. Compounds belonging to Group A are preferable because they have a group other than a hydrogen atom directly bonded to the para position of the phenolic oxygen atom, and therefore have even higher chemical stability. That is, Group A is a group of compounds that have even higher durability when used in organic light emitting devices. Further, A-24 to A-39 and A-52 to A-54 are compounds having a heterocyclic group, and can adjust the HOMO level and LUMO level.

Compounds belonging to Group B are compounds in which R ₂ and R ₉ or R ₃ and R ₈ are an alkyl group, an aryl group, or a heterocyclic group. In the compounds belonging to Group B, a group other than a hydrogen atom is bonded to one para-position of a phenolic oxygen atom, and a group other than a hydrogen atom is bonded to one of the adjacent carbon atoms at the para-position. Therefore, Group B is a compound group that has the second highest chemical stability after Group A, and has higher durability when used in an organic light emitting device. Furthermore, B-5, B-6, B-10, and B-11 are compounds having a heterocyclic group, and can adjust the HOMO level and LUMO level.

Compounds belonging to Group C are compounds in which R ₃ and R ₉ are an alkyl group, an aryl group, or a heterocyclic group. Group C has a group other than a hydrogen atom bonded to the carbon atom adjacent to the para-position to the phenolic oxygen atom, so it has the highest chemical stability next to Group B, and has higher durability when used in organic light-emitting devices. It is a group of compounds that have performance. Further, C-15 to C-18 and C-24 to C-26 are a group of compounds having a heterocyclic group, and can adjust the HOMO level and LUMO level.

Compounds belonging to Group D are compounds in which one of R ₂ , R ₃ , R ₈ , and R ₉ is an alkyl group, an aryl group, or a heterocyclic group. Group D, especially D-2 to D-7, have a para-position of the phenolic oxygen atom that is not protected by a group other than a hydrogen atom, so they are not as chemically stable as Groups A to C; This is a group of compounds that can easily improve properties and adjust the HOMO level and LUMO level.

≪Organic light emitting device≫
The organic light-emitting device of this embodiment has a pair of electrodes and a light-emitting layer disposed between the pair of electrodes, and the light-emitting layer includes a first compound, preferably a host, a second compound, Preferably, it has a guest.

A specific device structure of the organic light emitting device of this embodiment includes a multilayer device structure in which electrode layers and organic compound layers shown in (a) to (f) below are sequentially laminated on a substrate. Note that in any device configuration, the organic compound layer always includes a light-emitting layer containing a light-emitting material.
(a) Anode/Emissive layer/Cathode (b) Anode/Hole transport layer/Emissive layer/Electron transport layer/Cathode (c) Anode/Hole transport layer/Emissive layer/Electron transport layer/Electron injection layer/Cathode ( d) Anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / cathode (e) anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode ( f) Anode/hole transport layer/electron blocking layer/light emitting layer/hole blocking layer/electron transport layer/cathode However, these device configuration examples are only very basic device configurations, and device configurations are limited to these. It's not something you can do. For example, an insulating layer, an adhesive layer, or an interference layer is provided at the interface between an electrode and an organic compound layer, an electron transport layer or a hole transport layer is composed of two layers with different ionization potentials, and a light emitting layer is made of a light emitting material. Various layer configurations can be adopted, such as one composed of two different layers.

Further, the light emitting layer may be a single layer or a multilayer. Multilayer means a state in which a light-emitting layer and another light-emitting layer are laminated. For example, a light-emitting layer containing the host molecule, the organic compound of the present embodiment represented by general formula [1], and a guest molecule, and another light-emitting layer that emits light of a color different from that emitted by this light-emitting layer. The layers may be laminated. In this case, the emitted light color may be white or an intermediate color.

In the device configurations shown in (a) to (f) above, the configuration (f) is preferable because it has both an electron blocking layer and a hole blocking layer. In other words, in (f) having an electron blocking layer and a hole blocking layer, both hole and electron carriers can be reliably confined within the light emitting layer, resulting in an organic light emitting device with no carrier leakage and high luminous efficiency. .

The manner of extracting light output from the light emitting layer (element form) may be a so-called bottom emission method in which light is extracted from an electrode on the substrate side, or a so-called top emission method in which light is extracted from the opposite side of the substrate. Furthermore, a double-sided extraction method in which light is extracted from the substrate side and the opposite side of the substrate can also be adopted.

In the organic light emitting device of this embodiment, the organic compound of this embodiment is preferably included in the light emitting layer of the organic compound layers. At this time, the use of the compound contained in the light-emitting layer differs depending on the concentration within the light-emitting layer. Specifically, it is divided into a main component and a subcomponent depending on the concentration in the light emitting layer.

The compound serving as the main component is a compound having the largest mass ratio (concentration) among the compounds included in the light emitting layer, and is also called a host. The host is a compound that exists as a matrix around the luminescent material in the luminescent layer, and is primarily responsible for transporting carriers to the luminescent material and providing excitation energy to the luminescent material.

Further, a compound serving as a subsidiary component is a compound other than the main component, and depending on the function of the compound, it can be called a guest (dopant), a light emission assisting material, or a charge injection material. A guest, which is a type of subcomponent, is a compound (luminescent material) that is responsible for the main light emission within the luminescent layer. The light emission assisting material, which is a type of subcomponent, is a compound that helps the guest to emit light, and its mass ratio (concentration) in the light emitting layer is smaller than that of the host. The light emission assisting material is also called a second host due to its function.

The concentration of the host is preferably 50% by mass or more and 99% by mass or less, more preferably 70% by mass or more and 99% by mass or less, based on the total amount of the constituent materials of the light emitting layer. The concentration of the guest is from 0.01% by mass to less than 50% by mass, preferably from 0.1% by mass to 20% by mass, based on the total amount of the constituent materials of the light emitting layer. From the viewpoint of reducing concentration quenching, the guest concentration is particularly preferably 10% by mass or less. The concentration of the emission assist material is 0.1% by mass or more and less than 50% by mass, preferably 1% by mass or more and less than 50% by mass, based on the total amount of the constituent materials of the light emitting layer.

The guest may be contained uniformly throughout the layer in which the host is a matrix, or may be contained with a concentration gradient. Alternatively, a guest may be partially contained in a specific region within the layer, so that the light-emitting layer may have a region containing only the host and no guest.

In this embodiment, it is preferable that the organic compound of this embodiment is included in the light emitting layer as a host. In addition to the first compound and the second compound, the light-emitting layer may further contain a third compound (second host) for the purpose of assisting the transfer of excitons and carriers.

(2) First compound The first compound is preferably a host. The first compound is preferably the organic compound of the present embodiment represented by general formula [1].

(3) Second compound The second compound is preferably a guest. Guest molecules mainly involved in the luminescent function include fused ring compounds (e.g. fluorene derivatives, naphthalene derivatives, pyrene derivatives, perylene derivatives, tetracene derivatives, anthracene derivatives, rubrene, etc.), quinacridone derivatives, coumarin derivatives, stilbene derivatives, tris(8 - Organoaluminum complexes such as aluminum (quinolinolate), iridium complexes, platinum complexes, rhenium complexes, copper complexes, europium complexes, ruthenium complexes, and high Examples include molecular derivatives. Specific examples of compounds used as luminescent materials are shown below, but of course the compounds are not limited to these.

From the viewpoint of luminous efficiency in the organic light emitting device, the guest molecule is preferably a phosphorescent organometallic complex. Specific examples include iridium complexes, platinum complexes, rhenium complexes, copper complexes, europium complexes, and ruthenium complexes.

More preferably, the guest molecule is an organometallic complex represented by the following general formula [2] from the viewpoint of luminescence quantum yield.
M(L) _m (L') _n [2]

In formula [2], M is selected from iridium and platinum.
L and L' each represent a different bidentate ligand, and when a plurality of L or L's exist, they may be the same or different.
m is selected from an integer of 1 to 3, and n is selected from an integer of 0 to 2. However, when M is iridium, m+n=3, and when M is platinum, m+n=2.

The partial structure M(L) _m is represented by the following general formula [2-1].

In formula [2-1], R ₂₁ to R ₂₈ are a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted Substituted or unsubstituted silyl group, substituted or unsubstituted aryl group, substituted or unsubstituted heterocyclic group, substituted or unsubstituted amino group, substituent each independently selected from an unsubstituted or unsubstituted aryloxy group, a substituted or unsubstituted heteroaryloxy group, and a cyano group. Adjacent R ₂₁ to R ₂₈ may be bonded to each other to form a ring.

Examples of the halogen atom include, but are not limited to, fluorine, chlorine, bromine, and iodine. Among these, fluorine atoms are preferred.

Examples of the alkyl group include methyl group, ethyl group, normal propyl group, isopropyl group, normal butyl group, tertiary butyl group, secondary butyl group, octyl group, cyclohexyl group, 1-adamantyl group, 2-adamantyl group, etc. These include, but are not limited to.

Examples of the alkoxy group include, but are not limited to, a methoxy group, an ethoxy group, a propoxy group, a 2-ethyl-octyloxy group, a benzyloxy group, and the like.

Examples of the silyl group include, but are not limited to, trimethylsilyl group and triphenylsilyl group.

Examples of the aryl group include, but are not limited to, phenyl group, naphthyl group, indenyl group, biphenyl group, terphenyl group, fluorenyl group, phenanthryl group, fluoranthenyl group, triphenylenyl group, etc. .

Examples of the heterocyclic group include a pyridyl group, a pyrimidyl group, a pyrazyl group, a triazolyl group, an oxazolyl group, an oxadiazolyl group, a thiazolyl group, a thiadiazolyl group, a carbazolyl group, an acridinyl group, a phenanthrolyl group, a dibenzofuranyl group, and a dibenzothiophenyl group. etc., but are not limited to these. The heterocyclic group is preferably a heteroaryl group, and preferably a group bonded through carbon atoms.

Examples of the amino group include N-methylamino group, N-ethylamino group, N,N-dimethylamino group, N,N-diethylamino group, N-methyl-N-ethylamino group, N-benzylamino group, N-methyl-N-benzylamino group, N,N-dibenzylamino group, anilino group, N,N-diphenylamino group, N,N-dinaphthylamino group, N,N-difluorenylamino group, N -Phenyl-N-tolylamino group, N,N-ditolylamino group, N-methyl-N-phenylamino group, N,N-dianisorylamino group, N-mesityl-N-phenylamino group, N,N-dimesitylamino group group, N-phenyl-N-(4-tert-butylphenyl) amino group, N-phenyl-N-(4-trifluoromethylphenyl) amino group, N-piperidyl group, carbazolyl group, etc. It is not limited to.

Examples of the aryloxy group and heteroaryloxy group include, but are not limited to, a phenoxy group and a thienyloxy group.

Examples of substituents that an alkyl group, an alkoxy group, a silyl group, an aryl group, a heterocyclic group, an amino group, an aryloxy group, and a heteroaryloxy group may have include a deuterium atom; fluorine, chlorine, and bromine. , halogen atoms such as iodine; alkyl groups such as methyl group, ethyl group, normal propyl group, isopropyl group, normal butyl group, tertiary butyl group; alkoxy groups such as methoxy group, ethoxy group, propoxy group; dimethylamino group, Amino groups such as diethylamino, dibenzylamino, diphenylamino and ditolylamino groups; Aryloxy groups such as phenoxy; Aromatic hydrocarbon groups such as phenyl and biphenyl; Heterocyclic groups such as pyridyl and pyrrolyl ; Examples include, but are not limited to, a cyano group, a hydroxy group, and a thiol group.

Furthermore, adjacent R ₂₁ to R ₂₈ , preferably adjacent R ₂₁ to R ₂₄ or adjacent R ₂₅ to R ₂₈ may be bonded to each other to form a ring. Adjacent R ₂₁ to R ₂₈ combine with each other to form a ring, and the ring formed by combining R ₂₁ and R ₂₂ , R ₂₂ and R 23, R ₂₃ and R ₂₄ , and R ₂₁ to _{R 24} The benzene ring to which is bonded forms a condensed ring, or the ring formed by bonding R ₂₅ and R ₂₆ , R ₂₆ and R ₂₇ , or R 27 and R ₂₈ and _{R 25 to} R ₂₈ bond. This means that the pyridine rings form a fused ring. The ring formed by bonding adjacent R ₂₁ to R ₂₈ may be an aromatic ring.

The partial structure M(L') _n is represented by the following general formula [2-2].

In formula [2-2], R ₃₉ to R ₄₁ are a hydrogen atom, a deuterium atom, a halogen atom, a substituent-containing or unsubstituted alkyl group, a substituent-containing or unsubstituted alkoxy group, a substituted Substituted or unsubstituted silyl group, substituted or unsubstituted aryl group, substituted or unsubstituted heterocyclic group, substituted or unsubstituted amino group, substituent each independently selected from an unsubstituted or unsubstituted aryloxy group, a substituted or unsubstituted heteroaryloxy group, and a cyano group.

Specific examples of halogen atoms, alkyl groups, alkoxy groups, silyl groups, aryl groups, heterocyclic groups, amino groups, aryloxy groups, and heteroaryloxy groups include those similar to those explained for R ₂₁ to R ₂₈ . These include, but are not limited to. Further, as specific examples of substituents that an alkyl group, an alkoxy group, a silyl group, an aryl group, a heterocyclic group, an amino group, an aryloxy group, and a heteroaryloxy group may further have, R ₂₁ to R ₂₈ are Examples include, but are not limited to, those similar to those described above.

Among the organometallic complexes represented by the general formula [2], organometallic complexes in which the partial structure M(L) _m has three or more condensed rings are preferred. This is because the fused ring skeleton of three or more rings improves planarity and promotes energy transfer from the host molecule, leading to higher efficiency and improved durability. Examples of the fused ring having three or more rings include a phenanthrene ring, a triphenylene ring, a benzofluorene ring, a dibenzofuran ring, a dibenzothiophene ring, a benzonaphthofuran ring, a benzonaphthothiophene ring, a benzisoquinoline ring, and a naphthoisoquinoline ring.

Furthermore, in the general formula [2-1], at least one of R ₂₂ , R ₂₃ , R ₂₆ , and R ₂₇ is a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group. It is preferable that there be. This is because the planarity of the organometallic complex is improved as described above.

Specific examples of the partial structure M(L) _m of the organometallic complex serving as a guest are shown below, but the present invention is not limited thereto. In addition, in the specific examples shown below, coordinate bonds are shown by straight lines, dotted lines, or arrows.

In the above general formulas [Ir-5] to [Ir-8], [Ir-15] to [Ir-16], X' is an oxygen atom, a sulfur atom, a substituted or unsubstituted carbon atom, a substituted or unsubstituted carbon atom, selected from nitrogen atoms.

In the general formulas [Ir-2] to [Ir-8], adjacent R ₂₁ to R ₂₄ are bonded to each other to form a ring. In the general formulas [Ir-9] to [Ir-16], adjacent R ₂₅ to R ₂₈ are bonded to each other to form a ring. Further, in the general formulas [Ir-3] to [Ir-8], at least one of R ₂₁ to R ₂₄ is a phenyl group or a naphthyl group, and forms a ring with the adjacent group. In the general formulas [Ir-11] to [Ir-16], at least one of R ₂₅ to R ₂₈ is a phenyl group or a naphthyl group, and forms a ring with the adjacent group. Therefore, the general formulas [Ir-3] to [Ir-8], [Ir-11] to [Ir-16] may or may not further have an aryl group or a heterocyclic group. .

Among the metal complexes in which the partial structure M(L) _m is represented by the above general formulas [Ir-1] to [Ir-16], metal complexes having three or more fused rings as a ligand are more preferred. Specifically, the partial structure M(L) _m is a metal complex represented by the above general formulas [Ir-3] to [Ir-8], [Ir-11] to [Ir-16]. Specific examples thereof are shown below, but of course the invention is not limited to these.

Exemplary compounds belonging to Group AA to Group BB are metal complexes in which the partial structure M(L) _m is represented by the general formula [Ir-3], and are compounds having at least a phenanthrene ring in the ligand. These compounds have particularly excellent stability because their condensed rings consist of SP2 hybrid orbitals.

Exemplary compounds belonging to the CC group are metal complexes in which the partial structure M(L) _m is represented by the general formula [Ir-4], and are compounds having at least a triphenylene ring in the ligand. These compounds have particularly excellent stability because their condensed rings consist of SP2 hybrid orbitals.

Exemplary compounds belonging to the DD group are metal complexes in which the partial structure M(L) _m is represented by the general formulas [Ir-5] to [Ir-8], and the ligand includes at least a dibenzofuran ring, a dibenzothiophene ring, or a benzophene ring. It is a compound having a naphthofuran ring or a benzonaphthothiophene ring. These compounds contain oxygen atoms and sulfur atoms in their condensed rings, and the abundance of unshared electron pairs in these atoms can increase charge transport properties, making them particularly easy to adjust carrier balance. .

Exemplary compounds belonging to the EE group to the GG group are metal complexes in which the partial structure M(L) _m is represented by the general formula [Ir-6] to [Ir-8], and have at least a benzofluorene ring in the ligand. It is a compound. Since these compounds have a substituent at the 9-position of the fluorene ring in a direction perpendicular to the in-plane direction of the fluorene ring, it is possible to particularly reduce overlapping of the condensed rings. Therefore, it is a compound that has particularly excellent sublimation properties.

Exemplary compounds belonging to the HH group are metal complexes in which the partial structure M(L) _m is represented by the general formulas [Ir-11] to [Ir-13], and compounds having at least a benzoisoquinoline ring in the ligand. . These compounds contain an N atom in the condensed ring and can enhance charge transport properties due to the lone pair of electrons and high electronegativity of these atoms, so they are compounds in which the carrier balance can be particularly easily adjusted.

Exemplary compounds belonging to Group II are metal complexes in which the partial structure M(L) _m is represented by the general formula [Ir-14], and are compounds having at least a naphthoisoquinoline ring in the ligand. These compounds contain an N atom in the condensed ring and can enhance charge transport properties due to the lone pair of electrons and high electronegativity of these atoms, so they are compounds in which the carrier balance can be particularly easily adjusted.

(4) Other Compounds The organic light-emitting device according to the present embodiment may contain conventionally known low-molecular and high-molecular hole-injecting compounds or hole-transporting compounds, host compounds, and light-emitting compounds, as necessary. , an electron-injecting compound, an electron-transporting compound, or the like can be used together. Examples of these compounds are listed below.

As the hole injection and transport material, a material with high hole mobility is preferable so that holes can be easily injected from the anode and the injected holes can be transported to the light emitting layer. Further, in order to reduce deterioration of film quality such as crystallization in an organic light emitting device, a material having a high glass transition temperature is preferable. Examples of low-molecular and high-molecular materials with hole injection and transport properties include triarylamine derivatives, arylcarbazole derivatives, phenylenediamine derivatives, stilbene derivatives, phthalocyanine derivatives, porphyrin derivatives, poly(vinylcarbazole), poly(thiophene), and others. Examples include conductive polymers. Furthermore, the hole injection and transport material described above is also suitably used for an electron blocking layer. Specific examples of compounds used as hole injection and transport materials are shown below, but of course the compounds are not limited to these.

A compound other than the organic compound of this embodiment may be contained as a third compound as a light-emitting layer host or a light-emission assisting material contained in the light-emitting layer. Examples of the third compound include aromatic hydrocarbon compounds or derivatives thereof, carbazole derivatives, azine derivatives, xanthone derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, organoaluminum complexes such as tris(8-quinolinolate)aluminum, and organic Examples include beryllium complexes.

In particular, as the assist material, materials having a carbazole skeleton, materials having a triphenylene ring in the skeleton, and materials having a dibenzothiophene skeleton are preferable. This is because these materials have high electron-donating and electron-withdrawing properties, making it easy to adjust the HOMO level and LUMO level. Since the organic compound according to this embodiment has a CXD skeleton, the HOMO level and LUMO level tend to decrease. Therefore, a material having the above-mentioned skeleton that can adjust the HOMO and LUMO levels is particularly preferable as the assist material. When these assist materials are combined with the organic compound of this embodiment, good carrier balance can be achieved.

Specific examples of compounds used as the light-emitting layer host or light-emission assisting material contained in the light-emitting layer are shown below, but of course the present invention is not limited thereto. Among the specific examples below, materials having a carbazole skeleton that are preferable as assist materials are EM32 to EM38. Furthermore, materials having a triphenylene ring in their skeleton that are preferable as assist materials are EM10 to EM14, EM32, and EM39. Furthermore, materials having a dibenzothiophene skeleton that are preferable as assist materials are EM13, EM14, and EM28.

The electron-transporting material can be arbitrarily selected from those capable of transporting electrons injected from the cathode to the light-emitting layer, and is selected in consideration of the balance with the hole mobility of the hole-transporting material. . Examples of materials having electron transport properties include oxadiazole derivatives, oxazole derivatives, pyrazine derivatives, triazole derivatives, triazine derivatives, quinoline derivatives, quinoxaline derivatives, phenanthroline derivatives, organoaluminum complexes, fused ring compounds (e.g. fluorene derivatives, naphthalene derivatives, chrysene derivatives, anthracene derivatives, etc.). Furthermore, the above-mentioned electron transporting material is also suitably used for a hole blocking layer. Specific examples of compounds used as electron-transporting materials are shown below, but of course the compounds are not limited to these.

(5) Structure of organic light emitting device An organic light emitting device is provided by forming an insulating layer, a first electrode, an organic compound layer, and a second electrode on a substrate. A protective layer, a color filter, a microlens, etc. may be provided on the second electrode. When providing a color filter, a flattening layer may be provided between the color filter and the protective layer. The flattening layer can be made of acrylic resin or the like. The same applies to the case where a flattening layer is provided between the color filter and the microlens.

[substrate]
Examples of the substrate include quartz, glass, silicon wafer, resin, metal, and the like. Furthermore, switching elements such as transistors and wiring may be provided on the substrate, and an insulating layer may be provided thereon. The insulating layer may be made of any material as long as it can form a contact hole so that a wiring can be formed between it and the first electrode, and can ensure insulation from unconnected wiring. For example, resin such as polyimide, silicon oxide, silicon nitride, etc. can be used.

[electrode]
A pair of electrodes can be used as the electrodes. The pair of electrodes may be an anode and a cathode. When an electric field is applied in the direction in which the organic light-emitting element emits light, the electrode with the higher potential is the anode, and the other is the cathode. It can also be said that the electrode that supplies holes to the light emitting layer is the anode, and the electrode that supplies electrons is the cathode.

The material for the anode should preferably have a work function as large as possible. For example, metals such as gold, platinum, silver, copper, nickel, palladium, cobalt, selenium, vanadium, tungsten, mixtures containing these metals, alloys containing these metals, tin oxide, zinc oxide, indium oxide, and tin oxide. Metal oxides such as indium (ITO) and indium zinc oxide can be used. Conductive polymers such as polyaniline, polypyrrole, and polythiophene can also be used.

These electrode materials may be used alone or in combination of two or more. Further, the anode may be composed of a single layer or a plurality of layers.

When used as a reflective electrode, for example, chromium, aluminum, silver, titanium, tungsten, molybdenum, an alloy thereof, or a laminate thereof can be used. It is also possible for the above materials to function as a reflective film without having the role of an electrode. In addition, when used as a transparent electrode, a transparent conductive layer of oxide such as indium tin oxide (ITO) or indium zinc oxide can be used, but is not limited thereto. Photolithography technology can be used to form the electrodes.

On the other hand, the material for the cathode should preferably have a small work function. Examples include alkali metals such as lithium, alkaline earth metals such as calcium, single metals such as aluminum, titanium, manganese, silver, lead, and chromium, or mixtures containing these metals. Alternatively, an alloy that is a combination of these metals can also be used. For example, magnesium-silver, aluminum-lithium, aluminum-magnesium, silver-copper, zinc-silver, etc. can be used. Metal oxides such as indium tin oxide (ITO) can also be used. These electrode materials may be used alone or in combination of two or more. Further, the cathode may have a single layer structure or a multilayer structure. Among them, it is preferable to use silver, and in order to reduce agglomeration of silver, it is more preferable to use a silver alloy. The alloy ratio does not matter as long as silver agglomeration can be reduced. For example, the ratio of silver:other metal may be 1:1, 3:1, etc.

The cathode may be a top emission element using an oxide conductive layer such as ITO, or may be a bottom emission element using a reflective electrode such as aluminum (Al), and is not particularly limited. The method for forming the cathode is not particularly limited, but it is more preferable to use a direct current or an alternating current sputtering method because the coverage of the film is good and the resistance can be easily lowered.

[Organic compound layer]
The organic compound layer may be formed in a single layer or in multiple layers. When it has multiple layers, it may be called a hole injection layer, hole transport layer, electron blocking layer, light emitting layer, hole blocking layer, electron transport layer, or electron injection layer depending on its function. The organic compound layer is mainly composed of organic compounds, but may also contain inorganic atoms and inorganic compounds. For example, it may include copper, lithium, magnesium, aluminum, iridium, platinum, molybdenum, zinc, and the like. The organic compound layer may be disposed between the first electrode and the second electrode, or may be disposed in contact with the first electrode and the second electrode.

The organic compound layers (hole injection layer, hole transport layer, electron blocking layer, light emitting layer, hole blocking layer, electron transport layer, electron injection layer, etc.) constituting the organic light emitting device according to an embodiment of the present invention are , is formed by the method shown below.

The organic compound layer constituting the organic light emitting device according to an embodiment of the present invention can be formed using a dry process such as a vacuum evaporation method, an ionization evaporation method, sputtering, or plasma. Further, instead of the dry process, a wet process may be used in which the material is dissolved in an appropriate solvent and a layer is formed by a known coating method (for example, spin coating, dipping, casting method, LB method, inkjet method, etc.).

If the layer is formed by a vacuum deposition method, a solution coating method, or the like, crystallization is less likely to occur and the layer is excellent in stability over time. Furthermore, when forming a film by a coating method, the film can also be formed in combination with an appropriate binder resin.

Examples of the binder resin include, but are not limited to, polyvinyl carbazole resin, polycarbonate resin, polyester resin, ABS resin, acrylic resin, polyimide resin, phenol resin, epoxy resin, silicone resin, and urea resin. .

Further, these binder resins may be used alone as a homopolymer or a copolymer, or two or more types may be used as a mixture. Furthermore, if necessary, known additives such as plasticizers, antioxidants, and ultraviolet absorbers may be used in combination.

[Protective layer]
A protective layer may be provided on the second electrode. For example, by adhering glass provided with a moisture absorbent onto the second electrode, it is possible to reduce the intrusion of water and the like into the organic compound layer, thereby reducing the occurrence of display defects. In another embodiment, a passivation film made of silicon nitride or the like may be provided on the second electrode to reduce the infiltration of water or the like into the organic compound layer. For example, after forming the second electrode, the second electrode may be transferred to another chamber without breaking the vacuum, and a silicon nitride film having a thickness of 2 μm may be formed using a CVD method to form a protective layer. A protective layer may be provided using an atomic deposition method (ALD method) after film formation using a CVD method. The material of the film formed by the ALD method is not limited, but may be silicon nitride, silicon oxide, aluminum oxide, or the like. Silicon nitride may be further formed by CVD on the film formed by ALD. A film formed by the ALD method may have a smaller thickness than a film formed by the CVD method. Specifically, it may be 50% or less, or even 10% or less.

[Color filter]
A color filter may be provided on the protective layer. For example, a color filter that takes into account the size of the organic light emitting element may be provided on another substrate and bonded to the substrate on which the organic light emitting element is provided, or a color filter may be formed using photolithography technology on the protective layer shown above. , the color filter may be patterned. The color filter may be made of polymer.

[Planarization layer]
A flattening layer may be provided between the color filter and the protective layer. The planarization layer is provided for the purpose of reducing the unevenness of the underlying layer. It may also be referred to as a material resin layer without limiting the purpose. The planarization layer may be composed of an organic compound, and may be a low molecule or a polymer, but preferably a polymer.

The planarization layer may be provided above and below the color filter, and its constituent materials may be the same or different. Specific examples include polyvinyl carbazole resin, polycarbonate resin, polyester resin, ABS resin, acrylic resin, polyimide resin, phenol resin, epoxy resin, silicone resin, urea resin, and the like.

[Micro lens]
The organic light-emitting element or the organic light-emitting device may have an optical member such as a microlens on the light emission side. The microlens may be made of acrylic resin, epoxy resin, or the like. The purpose of the microlens may be to increase the amount of light extracted from the organic light emitting element or the organic light emitting device and to control the direction of the extracted light. The microlens may have a hemispherical shape. When the microlens has a hemispherical shape, among the tangents that touch the hemisphere, there is a tangent that is parallel to the insulating layer, and the point of contact between the tangent and the hemisphere is the vertex of the microlens. The apex of the microlens can be similarly determined in any cross-sectional view. That is, among the tangents that touch the semicircle of the microlens in the cross-sectional view, there is a tangent that is parallel to the insulating layer, and the point of contact between the tangent and the semicircle is the apex of the microlens.

It is also possible to define the midpoint of the microlens. In the cross section of the microlens, a line segment from a point where one circular arc ends to a point where another circular arc ends can be imagined, and the midpoint of the line segment can be called the midpoint of the microlens. The cross section for determining the apex and midpoint may be a cross section perpendicular to the insulating layer.

[Counter board]
A counter substrate may be provided on the planarization layer. The counter substrate is called a counter substrate because it is provided at a position corresponding to the above-described substrate. The constituent material of the counter substrate may be the same as that of the above-described substrate. The counter substrate may be the second substrate when the above-mentioned substrate is the first substrate.

[Pixel circuit]
An organic light emitting device having an organic light emitting element may have a pixel circuit connected to the organic light emitting element. The pixel circuit may be of an active matrix type that controls light emission of the first light emitting element and the second light emitting element independently. Active matrix type circuits may be voltage programming or current programming. The drive circuit has a pixel circuit for each pixel. A pixel circuit includes a light emitting element, a transistor that controls the luminance of the light emitting element, a transistor that controls the timing of light emission, a capacitor that holds the gate voltage of the transistor that controls the luminance, and a capacitor that is connected to GND without going through the light emitting element. It may include a transistor.

The light emitting device has a display area and a peripheral area arranged around the display area. The display area has a pixel circuit, and the peripheral area has a display control circuit. The mobility of the transistors forming the pixel circuit may be lower than the mobility of the transistors forming the display control circuit. The slope of the current-voltage characteristics of the transistors forming the pixel circuit may be smaller than the slope of the current-voltage characteristics of the transistors forming the display control circuit. The slope of the current-voltage characteristic can be measured by the so-called Vg-Ig characteristic. The transistors forming the pixel circuit are transistors connected to a light emitting element such as a first light emitting element.

[Pixel]
An organic light emitting device having an organic light emitting element may have a plurality of pixels. Each pixel has subpixels that emit different colors. For example, each subpixel may have an RGB emission color.

A region of a pixel, also called a pixel aperture, emits light. This area is the same as the first area. The pixel aperture may be less than or equal to 15 μm, and may be greater than or equal to 5 μm. More specifically, it may be 11 μm, 9.5 μm, 7.4 μm, 6.4 μm, etc. The distance between subpixels may be 10 μm or less, and specifically, may be 8 μm, 7.4 μm, or 6.4 μm.

Pixels can take a known arrangement form in a plan view. For example, it may be a stripe arrangement, a delta arrangement, a pentile arrangement, or a Bayer arrangement. The shape of the subpixel in a plan view may take any known shape. For example, a rectangle, a square such as a diamond, a hexagon, etc. Of course, it is not an exact figure, but if it has a shape close to a rectangle, it is included in the rectangle. The shape of the subpixel and the pixel arrangement can be used in combination.

(6) Device using organic light emitting device The organic light emitting device according to this embodiment can be used as a component of a display device or a lighting device. Other uses include exposure light sources for electrophotographic image forming apparatuses, backlights for liquid crystal display devices, and light emitting devices having a white light source with a color filter.

The display device has an image input section that inputs image information from an area CCD, linear CCD, memory card, etc., has an information processing section that processes the input information, and displays the input image on the display section. An image information processing device may also be used. The display device may include a plurality of pixels, and at least one of the plurality of pixels may include the organic light emitting element of this embodiment and a transistor connected to the organic light emitting element. At this time, the substrate may be a semiconductor substrate such as silicon, and the transistor may be a MOSFET formed on the substrate.

Further, the display section of the imaging device or the inkjet printer may have a touch panel function. The driving method for this touch panel function is not particularly limited, and may be an infrared method, a capacitance method, a resistive film method, or an electromagnetic induction method. Further, the display device may be used as a display section of a multi-function printer.

Next, a display device according to this embodiment will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing an example of a display device including an organic light emitting element and a transistor connected to the organic light emitting element. A transistor is an example of an active element. The transistor may be a thin film transistor (TFT).

FIG. 1A shows an example of a pixel that is a component of the display device according to this embodiment. The pixel has sub-pixels 10. The subpixels are divided into 10R, 10G, and 10B depending on their light emission. The emitted light color may be distinguished by the wavelength emitted from the light emitting layer, or the light emitted from the subpixel may be selectively transmitted or color-converted by a color filter or the like. Each subpixel 10 includes a reflective electrode as a first electrode 2 on an interlayer insulating layer 1 , an insulating layer 3 covering an end of the first electrode 2 , and an organic compound layer 4 covering the first electrode 2 and the insulating layer 3 . , a transparent electrode as the second electrode 5, a protective layer 6, and a color filter 7.

The interlayer insulating layer 1 may have a transistor or a capacitive element arranged thereunder or inside it. The transistor and the first electrode 2 may be electrically connected via a contact hole (not shown) or the like.

The insulating layer 3 is also called a bank or a pixel isolation film. It covers the end of the first electrode 2 and is arranged to surround the first electrode 2. The portion where the insulating layer 3 is not provided contacts the organic compound layer 4 and becomes a light emitting region.

The organic compound layer 4 includes a hole injection layer 41 , a hole transport layer 42 , a first light emitting layer 43 , a second light emitting layer 44 , and an electron transport layer 45 .

The second electrode 5 may be a transparent electrode, a reflective electrode, or a semi-transparent electrode.

The protective layer 6 reduces the penetration of moisture into the organic compound layer 4 . Although the protective layer 6 is illustrated as having a single layer, it may have multiple layers. Each layer may include an inorganic compound layer and an organic compound layer.

The color filter 7 is divided into 7R, 7G, and 7B depending on its color. The color filter 7 may be formed on a planarization film (not shown). Further, a resin protective layer (not shown) may be provided on the color filter 7. Further, the color filter 7 may be formed on the protective layer 6. Alternatively, it may be provided on a counter substrate such as a glass substrate and then bonded together.

The display device 100 in FIG. 1(b) includes an organic light emitting element 26 and a TFT 18, which is an example of a transistor. A substrate 11 made of glass, silicon, etc. and an insulating layer 12 are provided on top of the substrate 11. An active element such as a TFT 18 is arranged on the insulating layer 12, and a gate electrode 13 of the active element, a gate insulating film 14, and a semiconductor layer 15 are provided. TFT 18 has a drain electrode 16 and a source electrode 17. An insulating film 19 is provided above the TFT 18. An anode 21 and a source electrode 17 constituting an organic light emitting device 26 are connected through a contact hole 20 .

Note that the method of electrical connection between the electrodes (anode 21, cathode 23) included in the organic light emitting element 26 and the electrodes (source electrode 17, drain electrode 16) included in the TFT 18 is as shown in FIG. 1(b). It is not limited. That is, it is only necessary that either one of the anode 21 or the cathode 23 and either the source electrode 17 or the drain electrode 16 of the TFT 18 be electrically connected.

Although the organic compound layer 22 is illustrated as one layer in the display device 100 of FIG. 1(b), the organic compound layer 22 may be a plurality of layers. A first protective layer 24 and a second protective layer 25 are provided on the cathode 23 to reduce deterioration of the organic light emitting element 26.

Although a transistor is used as a switching element in the display device 100 of FIG. 1(b), other switching elements such as an MIM element may be used instead.

Further, the transistor used in the display device 100 in FIG. 1B is not limited to a thin film transistor having an active layer on an insulating surface of a substrate, but may be a transistor using a single crystal silicon wafer. Examples of the active layer include non-single-crystal silicon such as single-crystal silicon, amorphous silicon, and microcrystalline silicon, and non-single-crystal oxide semiconductors such as indium zinc oxide and indium gallium zinc oxide. Note that the thin film transistor is also called a TFT element.

The transistor included in the display device 100 in FIG. 1(b) may be formed within a substrate such as a Si substrate. Here, "formed in a substrate" means that the transistor is fabricated by processing the substrate itself, such as a Si substrate. In other words, having a transistor within the substrate can also be considered to mean that the substrate and the transistor are integrally formed.

The luminance of the organic light-emitting device according to this embodiment is controlled by a TFT, which is an example of a switching element, and by providing the organic light-emitting devices in a plurality of planes, images can be displayed with the luminance of each device. Note that the switching element according to this embodiment is not limited to a TFT, but may be a transistor formed of low-temperature polysilicon, or an active matrix driver formed on a substrate such as a Si substrate. On the substrate can also be referred to as inside the substrate. Whether a transistor is provided within the substrate or a TFT is used is selected depending on the size of the display section. For example, if the size is about 0.5 inch, it is preferable to provide the organic light emitting element on the Si substrate.

FIG. 2 is a schematic diagram showing an example of a display device according to this embodiment. The display device 1000 may include a touch panel 1003, a display panel 1005, a frame 1006, a circuit board 1007, and a battery 1008 between an upper cover 1001 and a lower cover 1009. Flexible printed circuits FPCs 1002 and 1004 are connected to the touch panel 1003 and the display panel 1005. A transistor is printed on the circuit board 1007. The battery 1008 may not be provided unless the display device is a portable device, or may be provided at a different location even if the display device is a portable device.

The display device according to this embodiment may include color filters having red, green, and blue colors. In the color filter, the red, green, and blue colors may be arranged in a delta arrangement.

The display device according to this embodiment may be used as a display section of a mobile terminal. In that case, it may have both a display function and an operation function. Examples of mobile terminals include mobile phones such as smartphones, tablets, head-mounted displays, and the like.

The display device according to this embodiment may be used as a display section of an imaging device that includes an optical section that has a plurality of lenses and an image sensor that receives light that has passed through the optical section. The imaging device may include a display unit that displays information acquired by the imaging device. Furthermore, the display section may be a display section exposed to the outside of the imaging device, or a display section disposed within the viewfinder. The imaging device may be a digital camera or a digital video camera.

FIG. 3(a) is a schematic diagram showing an example of an imaging device according to this embodiment. The imaging device 1100 may include a viewfinder 1101, a rear display 1102, an operation unit 1103, and a housing 1104. The viewfinder 1101 may include a display device according to this embodiment. In that case, the display device may display not only the image to be captured, but also environmental information, imaging instructions, and the like. The environmental information may include the intensity of external light, the direction of external light, the moving speed of the subject, the possibility that the subject will be blocked by a shielding object, and the like.

Since the optimum timing for imaging is only a short time, it is better to display information as early as possible. Therefore, it is preferable to use a display device using the organic light emitting device of this embodiment. This is because organic light emitting devices have a fast response speed. Display devices using organic light-emitting elements can be used more favorably than these devices and liquid crystal display devices, which require high display speed.

The imaging device 1100 has an optical section (not shown). The optical section has a plurality of lenses and forms an image on an image sensor housed in the housing 1104. The focus of the plural lenses can be adjusted by adjusting their relative positions. This operation can also be performed automatically. The imaging device may also be called a photoelectric conversion device. The photoelectric conversion device does not take images sequentially, but can include a method of detecting a difference from a previous image, a method of cutting out an image from a constantly recorded image, etc. as an imaging method.

FIG. 3(b) is a schematic diagram showing an example of the electronic device according to the present embodiment. Electronic device 1200 includes a display section 1201, an operation section 1202, and a housing 1203. The housing 1203 may include a circuit, a printed circuit board including the circuit, a battery, and a communication section. The operation unit 1202 may be a button or a touch panel type reaction unit. The operation unit 1202 may be a biometric recognition unit that recognizes a fingerprint and performs unlocking and the like. An electronic device having a communication section can also be called a communication device. The electronic device 1200 may further have a camera function by including a lens and an image sensor. An image captured by the camera function is displayed on the display unit 1201. Examples of the electronic device 1200 include a smartphone, a notebook computer, and the like.

FIG. 4 is a schematic diagram showing an example of a display device according to this embodiment. FIG. 4A shows a display device such as a television monitor or a PC monitor. The display device 1300 has a frame 1301 and a display portion 1302. The display portion 1302 may use the light emitting element according to this embodiment. The display device 1300 has a frame 1301 and a base 1303 that supports a display portion 1302. The base 1303 is not limited to the form shown in FIG. 4(a). The lower side of the picture frame 1301 may also serve as a base. Further, the frame 1301 and the display portion 1302 may be curved. The radius of curvature may be greater than or equal to 5000 mm and less than or equal to 6000 mm.

FIG. 4(b) is a schematic diagram showing another example of the display device according to this embodiment. The display device 1310 in FIG. 4B is configured to be foldable, and is a so-called foldable display device. The display device 1310 includes a first display section 1311, a second display section 1312, a housing 1313, and a bending point 1314. The first display section 1311 and the second display section 1312 may include the light emitting element according to this embodiment. The first display section 1311 and the second display section 1312 may be one seamless display device. The first display section 1311 and the second display section 1312 can be separated at a bending point. The first display section 1311 and the second display section 1312 may each display different images, or the first and second display sections may display one image.

FIG. 5(a) is a schematic diagram showing an example of the lighting device according to this embodiment. The lighting device 1400 may include a housing 1401, a light source 1402, a circuit board 1403, an optical filter 1404 that transmits light emitted from the light source 1402, and a light diffusing section 1405. The light source 1402 may include an organic light emitting device according to this embodiment. The optical filter 1404 may be a filter that improves the color rendering properties of the light source. The light diffusing unit 1405 can effectively diffuse the light from a light source, such as when lighting up, and can deliver the light to a wide range. The optical filter 1404 and the light diffusing section 1405 may be provided on the light exit side of the illumination. If necessary, a cover may be provided on the outermost side.

The lighting device is, for example, a device that illuminates a room. The lighting device may emit white, daylight white, or any other color from blue to red. It may have a dimmer circuit that adjusts the light and a color adjustment circuit that adjusts the color of the emitted light. The lighting device may include the organic light emitting device of this embodiment and a power supply circuit connected thereto. The power supply circuit is a circuit that converts alternating current voltage to direct current voltage. Further, white has a color temperature of 4200K, and neutral white has a color temperature of 5000K. The lighting device may have a color filter.

Furthermore, the lighting device according to this embodiment may include a heat radiation section. The heat dissipation section radiates heat within the device to the outside of the device, and may be made of metal with high specific heat, liquid silicon, or the like.

FIG. 5(b) is a schematic diagram of an automobile, which is an example of a moving object according to the present embodiment. The automobile has a tail lamp, which is an example of a lamp. The automobile 1500 may have a tail lamp 1501, and the tail lamp may be turned on when a brake operation or the like is performed.

The tail lamp 1501 may include an organic light emitting device according to this embodiment. The tail lamp 1501 may include a protection member that protects the organic light emitting element. The protective member may be made of any material as long as it has a certain degree of strength and is transparent, but it is preferably made of polycarbonate or the like. Furandicarboxylic acid derivatives, acrylonitrile derivatives, etc. may be mixed with polycarbonate.

The automobile 1500 may have a body 1503 and a window 1502 attached thereto. The window 1502 may be a transparent display as long as it is not a window for checking the front and rear of the automobile. The transparent display may include an organic light emitting device according to this embodiment. In this case, constituent materials such as electrodes included in the organic light emitting element are made of transparent members.

The mobile object according to this embodiment may be a ship, an aircraft, a drone, or the like. The moving body may include a body and a lamp provided on the body. The light may emit light to indicate the position of the aircraft. The lamp includes the organic light emitting device according to this embodiment.

With reference to FIG. 6, application examples of the display devices of the above-described embodiments will be described. The display device can be applied to systems that can be worn as wearable devices, such as smart glasses, HMDs, and smart contacts. An imaging display device used in such an application example includes an imaging device capable of photoelectrically converting visible light and a display device capable of emitting visible light.

FIG. 6(a) is a schematic diagram showing an example of a wearable device according to an embodiment of the present invention. Glasses 1600 (smart glasses) according to one application example will be described using FIG. 6(a). An imaging device 1602 such as a CMOS sensor or a SPAD is provided on the front side of the lens 1601 of the glasses 1600. Further, the display device of each embodiment described above is provided on the back side of the lens 1601.

Glasses 1600 further include a control device 1603. The control device 1603 functions as a power source that supplies power to the imaging device 1602 and the display device. Further, the control device 1603 controls the operations of the imaging device 1602 and the display device. An optical system for condensing light onto an imaging device 1602 is formed in the lens 1601.

FIG. 6(b) is a schematic diagram showing another example of a wearable device according to an embodiment of the present invention. Glasses 1610 (smart glasses) according to one application example will be described using FIG. 6(b). The glasses 1610 include a control device 1612, and the control device 1612 is equipped with an imaging device corresponding to the imaging device 1602 in FIG. 6(a) and a display device. The lens 1611 is formed with an optical system for projecting light emitted from the imaging device in the control device 1612 and the display device, and an image is projected onto the lens 1611. The control device 1612 functions as a power source that supplies power to the imaging device and the display device, and controls the operations of the imaging device and the display device.

The control device 1612 may include a line-of-sight detection unit that detects the wearer's line of sight. Infrared rays may be used to detect line of sight. The infrared light emitting unit emits infrared light to the eyeballs of the user who is gazing at the displayed image. A captured image of the eyeball is obtained by detecting the reflected light of the emitted infrared light from the eyeball by an imaging section having a light receiving element. By having a reduction means for reducing light emitted from the infrared light emitting section to the display section in plan view, deterioration in image quality is reduced. The user's line of sight with respect to the displayed image is detected from the captured image of the eyeball obtained by infrared light imaging. Any known method can be applied to line of sight detection using a captured image of the eyeball. As an example, a line of sight detection method based on a Purkinje image by reflection of irradiated light on the cornea can be used. More specifically, line of sight detection processing is performed based on the pupillary corneal reflex method. Using the pupillary corneal reflex method, the user's line of sight is detected by calculating a line of sight vector representing the direction (rotation angle) of the eyeball based on the pupil image and Purkinje image included in the captured image of the eyeball. Ru.

A display device according to an embodiment of the present invention may include an imaging device having a light receiving element, and may control a display image of the display device based on user's line-of-sight information from the imaging device. Specifically, the display device determines a first viewing area that the user gazes at and a second viewing area other than the first viewing area based on the line-of-sight information. The first viewing area and the second viewing area may be determined by the control device of the display device, or may be determined by an external control device and may be received. In the display area of the display device, the display resolution of the first viewing area may be controlled to be higher than the display resolution of the second viewing area. That is, the resolution of the second viewing area may be lower than that of the first viewing area.

In addition, the display area has a first display area and a second display area different from the first display area, and based on line-of-sight information, priority is determined from the first display area and the second display area. The area where the value is high is determined. The first viewing area and the second viewing area may be determined by the control device of the display device, or may be determined by an external control device and may be received. The resolution of areas with high priority may be controlled to be higher than the resolution of areas other than areas with high priority. In other words, the resolution of an area with a relatively low priority may be lowered.

Note that AI may be used to determine the first viewing area and the area with high priority. AI is a model configured to estimate the angle of line of sight and the distance to the object in front of the line of sight from the image of the eyeball, using the image of the eyeball and the direction in which the eyeball was actually looking in the image as training data. It's good to be there. The AI program may be included in a display device, an imaging device, or an external device. If the external device has it, it is transmitted to the display device via communication.

When display control is performed based on visual detection, it can be preferably applied to smart glasses that further include an imaging device that captures an image of the outside. Smart glasses can display captured external information in real time.

FIG. 7A is a schematic diagram showing an example of an image forming apparatus according to an embodiment of the present invention. The image forming apparatus 40 is an electrophotographic image forming apparatus, and includes a photoreceptor 27, an exposure light source 28, a charging section 30, a developing section 31, a transfer device 32, a conveying roller 33, and a fixing device 35. Light 29 is irradiated from the exposure light source 28, and an electrostatic latent image is formed on the surface of the photoreceptor 27. This exposure light source 28 has an organic light emitting device according to this embodiment. The developing section 31 contains toner and the like. The charging section 30 charges the photoreceptor 27. The transfer device 32 transfers the developed image onto a recording medium 34. The conveyance roller 33 conveys the recording medium 34. The recording medium 34 is, for example, paper. The fixing device 35 fixes the image formed on the recording medium 34.

FIGS. 7(b) and 7(c) are diagrams showing the exposure light source 28, and are schematic diagrams showing a state in which a plurality of light emitting sections 36 are arranged on a long substrate. The arrow 37 is a direction parallel to the axis of the photoreceptor, and represents the column direction in which the organic light emitting elements are arranged. This column direction is the same as the direction of the axis around which the photoreceptor 27 rotates. This direction can also be called the long axis direction of the photoreceptor 27. FIG. 7B shows a configuration in which the light emitting section 36 is arranged along the long axis direction of the photoreceptor 27. In FIG. FIG. 7(c) is a different form from FIG. 7(b), in which the light emitting parts 36 are arranged alternately in the column direction in each of the first column and the second column. The first column and the second column are arranged at different positions in the row direction. In the first row, a plurality of light emitting sections 36 are arranged at intervals. The second row has light emitting parts 36 at positions corresponding to the spacing between the light emitting parts 36 in the first row. That is, a plurality of light emitting sections 36 are arranged at intervals also in the row direction. The arrangement in FIG. 7C can also be expressed as, for example, a lattice arrangement, a houndstooth arrangement, or a checkered pattern.

As explained above, by using the device using the organic light emitting element according to this embodiment, stable display with good image quality can be achieved even for long periods of time.

≪Included configurations≫
The disclosure of this embodiment includes the following configurations.
(Configuration 1)
An organic compound represented by the above general formula [1].
(Configuration 2)
At least one of R ₂ , R ₃ , R ₈ , and R ₉ is selected from a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group. The organic compound according to configuration 1.
(Configuration 3)
According to configuration 1 or 2, at least one of R ₂ , R ₃ , R ₈ , and R ₉ is selected from a substituted or unsubstituted aryl group and a substituted or unsubstituted heterocyclic group. organic compounds.
(Configuration 4)
At least two of R ₂ , R ₃ , R ₈ , and R ₉ are selected from a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group. The organic compound according to configuration 1 or 2.
(Configuration 5)
At least one of R ₂ and R ₃ and at least one of R ₈ and R ₉ are a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocycle. The organic compound according to structure 1 or 2, characterized in that the organic compound is selected from the group consisting of:
(Configuration 6)
The organic compound according to configuration 5, wherein R ₂ and R ₈ are selected from a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group.

(Configuration 7)
comprising a pair of electrodes and a light emitting layer disposed between the pair of electrodes,
The light emitting layer has a first compound and a second compound,
An organic light emitting device, wherein the first compound is an organic compound according to any one of Structures 1 to 6.
(Configuration 8)
7. The organic light-emitting device according to configuration 7, wherein the second compound is an organometallic complex represented by the general formula [2].
(Configuration 9)
9. The organic light emitting device according to configuration 8, wherein M is iridium.
(Configuration 10)
10. The organic light-emitting device according to configuration 8 or 9, wherein the partial structure M(L) _m has three or more condensed rings.
(Configuration 11)
The fused ring of three or more rings is any one of a phenanthrene ring, a triphenylene ring, a benzofluorene ring, a dibenzofuran ring, a dibenzothiophene ring, a benzonaphthofuran ring, a benzonaphthothiophene ring, a benzisoquinoline ring, and a naphthoisoquinoline ring. The organic light emitting device according to feature 10.
(Configuration 12)
In the general formula [2-1], at least one of R ₂₂ , R ₂₃ , R ₂₆ , and R ₂₇ is a substituted or unsubstituted aryl group, a substituted or unsubstituted hetero 12. The organic light-emitting device according to any one of structures 8 to 11, which is selected from cyclic groups.

(Configuration 13)
13. The organic light emitting device according to any one of structures 7 to 12, wherein the light emitting layer further contains a third compound.
(Configuration 14)
14. The organic light-emitting device according to configuration 13, wherein the third compound has at least a carbazole skeleton.
(Configuration 15)
14. The organic light-emitting device according to configuration 13, wherein the third compound has at least a triphenylene ring in its skeleton.
(Configuration 16)
14. The organic light-emitting device according to configuration 13, wherein the third compound has at least a dibenzothiophene skeleton.
(Configuration 17)
Any of configurations 7 to 16, further comprising another light emitting layer disposed in a stacked manner with the light emitting layer, and the another light emitting layer emits light in a color different from that emitted by the light emitting layer. The organic light-emitting device described in Crab.
(Configuration 18)
18. The organic light-emitting device according to configuration 17, which emits white light.

(Configuration 19)
A display comprising a plurality of pixels, at least one of the plurality of pixels including the organic light-emitting element according to any one of configurations 7 to 18, and a transistor connected to the organic light-emitting element. Device.
(Configuration 20)
It has an optical section having a plurality of lenses, an image sensor that receives light that has passed through the optical section, and a display section that displays an image captured by the image sensor,
19. A photoelectric conversion device, wherein the display section includes the organic light emitting element according to any one of Structures 7 to 18.
(Configuration 21)
It is characterized by having a display section having the organic light emitting element according to any one of configurations 7 to 18, a casing in which the display section is provided, and a communication section provided in the casing and communicating with the outside. and electronic equipment.
(Configuration 22)
19. A lighting device comprising: a light source having the organic light emitting element according to any one of Structures 7 to 18; and a light diffusion section or an optical filter that transmits light emitted from the light source.
(Configuration 23)
19. A mobile object comprising: a lamp having the organic light emitting element according to any one of configurations 7 to 18; and a body provided with the lamp.
(Configuration 24)
19. An exposure light source for an electrophotographic image forming apparatus, comprising the organic light emitting element according to any one of Structures 7 to 18.

Examples will be described below. Note that the present invention is not limited to these.

<Example 1 (Synthesis of Exemplary Compound A-1)>

[Reaction step 1 (synthesis of intermediate compound Int1-1)]
The reagents and solvent shown below were put into a 200 mL eggplant flask.
Resorcinol (manufactured by Tokyo Chemical Industry): 5.00g (45.4mmol)
5-Bromo-2-fluorobenzonitrile (manufactured by Tokyo Kasei Kogyo): 19.8g (98.8mmol)
Potassium carbonate: 15.0g (108mmol)
Dimethyl sulfoxide: 62mL

The reaction solution was heated under nitrogen at 80° C. with stirring for 12 hours. After the reaction was completed, the reaction solution was cooled to room temperature, poured into ice water, and stirred for 1 hour. The precipitated solid was collected by filtration, washed with ion-exchanged water, and then dried in a vacuum dryer at 80° C. for 12 hours. The obtained crude product was recrystallized from a dichloromethane/heptane solvent to obtain 18.1 g of Int1-1 (yield: 85%).

[Reaction step 2 (synthesis of intermediate compound Int1-2)]
The reagents and solvent shown below were put into a 200 mL eggplant flask.
Int1-1: 5.00g (10.6mmol)
Sodium hydroxide: 5.32g (133mmol)
Ion exchange water: 21mL
Ethanol: 80mL

The reaction solution was heated to reflux for 6 hours with stirring under nitrogen. After the reaction was completed, the reaction solution was cooled to room temperature, and then 2N hydrochloric acid was added dropwise to the reaction solution until the pH reached 1 to 2. The precipitated solid was collected by filtration and then dried in a vacuum dryer at 80° C. for 12 hours to obtain 5.30 g of Int1-2 (yield 98%).

[Reaction step 3 (synthesis of intermediate compound Int1-3)]
The reagents and solvent shown below were put into a 100 mL eggplant flask.
Int1-2: 5.00g (9.84mmol)
Concentrated sulfuric acid: 17mL

The reaction solution was heated under nitrogen at 80° C. with stirring for 12 hours. After the reaction was completed, the reaction solution was cooled to room temperature, poured into crushed ice, and stirred for 1 hour. The precipitated solid was collected by filtration, washed with ion-exchanged water, and then dried in a vacuum dryer at 80° C. for 12 hours. The obtained crude product was recrystallized from a dichloromethane/methanol solvent to obtain 4.18 g of Int1-3 (yield 90%).

[Reaction Step 4 (Synthesis of Exemplary Compound A-1)]

The reagents and solvent shown below were put into a 50 mL eggplant flask.
Int1-3: 0.500g (1.06mmol)
Phenylboronic acid (manufactured by Tokyo Chemical Industry): 0.284g (2.33mmol)
Sodium carbonate: 0.617g (5.83mmol)
Tetrakis(triphenylphosphine)palladium(0): 0.122g (0.106mmol)
Toluene: 10mL
Ion exchange water: 3mL

The reaction solution was heated to reflux under nitrogen with stirring for 18 hours. After the reaction was completed, the organic layer was cooled to room temperature, separated, dried over magnesium sulfate, and filtered. The solvent of the obtained filtrate was distilled off under reduced pressure, and the precipitated solid was purified using a silica gel column (chloroform:heptane=3:1). The obtained crystals were dried in a vacuum dryer at 80° C. for 12 hours to obtain 0.420 g of Exemplary Compound A-1 (yield: 85%).

The M ⁺ value of this compound, 466.1, was confirmed by MALDI-TOF MS (matrix-assisted ionization-time-of-flight mass spectrometry).

<Examples 2 to 6 (Synthesis of exemplified compounds)>
The exemplified compounds shown in Table 2 were synthesized in the same manner as in Example 1, except that in reaction step 4 of Example 1, phenylboronic acid was changed to the boronic acid compounds shown in Table 2.

<Example 7 (Synthesis of Exemplary Compound C-1)>
[Reaction steps 1 to 3 (synthesis of intermediate compounds Int2-1 to Int2-3)]

In reaction step 1 of Example 1, the intermediate compound Int2 was prepared in the same manner as reaction steps 1 to 3 of Example 1, except that 5-bromo-2-fluorobenzonitrile was changed to 4-bromo-2-fluorobenzonitrile. -1 to 2-3 were synthesized.

[Reaction Step 4 (Synthesis of Exemplary Compound C-1)]

Exemplary compound C-1 was synthesized in the same manner as reaction step 4 of Example 1, except that in reaction step 4 of Example 1, the reaction step intermediate compound Int1-3 was changed to intermediate compound Int2-3.

<Examples 8 to 12 (Synthesis of exemplified compounds)>
The exemplified compounds shown in Table 3 were synthesized in the same manner as in Example 7, except that in reaction step 4 of Example 7, phenylboronic acid was changed to the boronic acid compound shown in Table 3.

<Examples 13 to 14 (Synthesis of exemplified compounds A-40 and C-19)>
In reaction step 1 of Example 1, 5-bromo-2-fluorobenzonitrile was converted into 5-methyl-2-fluorobenzonitrile (manufactured by Tokyo Kasei Kogyo) or 4-methyl-2-fluorobenzonitrile (manufactured by Tokyo Kasei Kogyo). ) Exemplary compounds A-40 and C-19 were synthesized in the same manner as in reaction steps 1 to 3 of Example 1, except for changing to

<Comparative Example 1 (CXD synthesis)>
CXD was carried out in the same manner as reaction steps 1 to 3 of Example 1, except that in reaction step 1 of Example 1, 5-bromo-2-fluorobenzonitrile was changed to 2-fluorobenzonitrile (manufactured by Tokyo Kasei Kogyo). Synthesized.

<Example 15>
An organic light emitting device with a bottom emission type structure in which an anode, a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, and a cathode are sequentially formed on a substrate. was created.

First, an ITO electrode (anode) was formed by forming an ITO film on a glass substrate and subjecting it to desired patterning. At this time, the film thickness of the ITO electrode was set to 100 nm. The substrate on which the ITO electrode was formed in this manner was used as an ITO substrate in the following steps. Next, vacuum evaporation was performed by resistance heating in a vacuum chamber at 1.33×10 ⁻⁴ Pa to successively form an organic compound layer and an electrode layer shown in Table 4 on the ITO substrate. At this time, the electrode area of the opposing electrodes (metal electrode layer, cathode) was set to 3 mm ² .

The characteristics of the obtained device were measured and evaluated. The maximum emission wavelength of the light emitting device was 522 nm, and the maximum external quantum efficiency (E.Q.E.) was 13%.

Further, a continuous drive test was conducted at a current density of 100 mA/cm ² and the time required for the brightness deterioration rate to reach 5% was measured. When the time when the brightness deterioration rate of Comparative Example 2 reached 5% was set as a reference (1.0), the 5% brightness deterioration time of this example was expressed as a ratio of 1.4.

In this example, the current-voltage characteristics were specifically measured using a microammeter 4140B manufactured by Hewlett-Packard, and the luminance was measured using BM7 manufactured by Topcon.

<Examples 16 to 24, Comparative Example 2>
An organic light emitting device was produced in the same manner as in Example 15, except that the host and guest were changed to the compounds shown in Table 5 as appropriate. The characteristics of the obtained device were measured and evaluated in the same manner as in Example 15. The measurement results are shown in Table 5.

<Example 25>
An organic light-emitting device was produced in the same manner as in Example 15, except that the organic compound layer and electrode layer shown in Table 6 were continuously formed.

The characteristics of the obtained device were measured and evaluated in the same manner as in Example 15. The maximum emission wavelength of the light emitting device was 522 nm, and the maximum external quantum efficiency (E.Q.E.) was 19%. Furthermore, when the time when the brightness deterioration rate of Comparative Example 3 reached 5% was taken as the reference (1.0), the 5% brightness deterioration time of this example was expressed as a ratio of 1.4. .

<Examples 26 to 34, Comparative Example 3>
An organic light-emitting device was produced in the same manner as in Example 25, except that the compounds shown in Table 7 were changed as appropriate. The characteristics of the obtained device were measured and evaluated in the same manner as in Example 25. The measurement results are shown in Table 7.

As shown in Table 7, by using the organic compound of this embodiment as a host and further using a material having a carbazole skeleton, triphenylene skeleton, etc. suitable for combination with the organic compound of this embodiment as a second host material, The luminous efficiency and lifetime characteristics of the device have been improved.

Reference Signs List 1: interlayer insulating layer, 2: first electrode, 3: insulating layer, 4: organic compound layer, 5: second electrode, 6: protective layer, 7: color filter, 10: subpixel, 11: substrate, 12: Insulating layer, 13: Gate electrode, 14: Gate insulating film, 15: Semiconductor layer, 16: Drain electrode, 17: Source electrode, 18: TFT, 19: Insulating film, 20: Contact hole, 21: Anode, 22: Organic Compound layer, 23: cathode, 24: first protective layer, 25: second protective layer, 26: organic light emitting element, 100: display device

Claims (24)

An organic compound represented by the following general formula [1].

In the general formula [1], R ₁ to R ₁₀ are each independently selected from a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group. It will be done. However, at least one of R ₂ , R ₃ , R ₈ , and R ₉ is a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group. To be elected. At least one of R ₂ , R ₃ , R ₈ , and R ₉ is selected from a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group. The organic compound according to claim 1. 3. The method according to claim 2, wherein at least one of R ₂ , R ₃ , R ₈ , and R ₉ is selected from a substituted or unsubstituted aryl group and a substituted or unsubstituted heterocyclic group. organic compound. At least two of R ₂ , R ₃ , R ₈ , and R ₉ are selected from a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group. The organic compound according to claim 2. At least one of R ₂ and R ₃ and at least one of R ₈ and R ₉ are a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocycle. 3. The organic compound according to claim 2, wherein the organic compound is selected from the group consisting of: 6. The organic compound according to claim 5, wherein _R2 and _R8 are selected from a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group. comprising a pair of electrodes and a light emitting layer disposed between the pair of electrodes,
The light emitting layer has a first compound and a second compound,
An organic light emitting device, wherein the first compound is the organic compound according to any one of claims 1 to 6. The organic light emitting device according to claim 7, wherein the second compound is an organometallic complex represented by the following general formula [2].
M(L) _m (L') _n [2]
In general formula [2], M is selected from iridium and platinum.
L and L' each represent a different bidentate ligand, and when a plurality of L or L's exist, they may be the same or different.
m is selected from an integer of 1 to 3, and n is selected from an integer of 0 to 2. However, when M is iridium, m+n=3, and when M is platinum, m+n=2.
The partial structure M(L) _m is represented by the following general formula [2-1].

In the general formula [2-1], R ₂₁ to R ₂₈ are a hydrogen atom, a deuterium atom, a halogen atom, a substituent-containing or unsubstituted alkyl group, a substituent-containing or unsubstituted alkoxy group, Substituted or unsubstituted silyl group, substituted or unsubstituted aryl group, substituted or unsubstituted heterocyclic group, substituted or unsubstituted amino group, substituted Each is independently selected from a substituted or unsubstituted aryloxy group, a substituted or unsubstituted heteroaryloxy group, and a cyano group. Adjacent R ₂₁ to R ₂₈ may be bonded to each other to form a ring.
The partial structure M(L') _n is represented by the following general formula [2-2].

In the general formula [2-2], R ₃₉ to R ₄₁ are a hydrogen atom, a deuterium atom, a halogen atom, a substituent-containing or unsubstituted alkyl group, a substituent-containing or unsubstituted alkoxy group, Substituted or unsubstituted silyl group, substituted or unsubstituted aryl group, substituted or unsubstituted heterocyclic group, substituted or unsubstituted amino group, substituted Each is independently selected from a substituted or unsubstituted aryloxy group, a substituted or unsubstituted heteroaryloxy group, and a cyano group. The organic light emitting device according to claim 8, wherein the M is iridium. 9. The organic light emitting device according to claim 8, wherein the partial structure M(L) _m has three or more condensed rings. The fused ring of three or more rings is any one of a phenanthrene ring, a triphenylene ring, a benzofluorene ring, a dibenzofuran ring, a dibenzothiophene ring, a benzonaphthofuran ring, a benzonaphthothiophene ring, a benzisoquinoline ring, and a naphthoisoquinoline ring. The organic light emitting device according to claim 10. In the general formula [2-1], at least one of R ₂₂ , R ₂₃ , R ₂₆ , and R ₂₇ is a substituted or unsubstituted aryl group, a substituted or unsubstituted hetero The organic light emitting device according to claim 8, characterized in that it is selected from cyclic groups. 8. The organic light emitting device according to claim 7, wherein the light emitting layer further contains a third compound. 14. The organic light emitting device according to claim 13, wherein the third compound has at least a carbazole skeleton. 14. The organic light emitting device according to claim 13, wherein the third compound has at least a triphenylene ring in its skeleton. 14. The organic light emitting device according to claim 13, wherein the third compound has at least a dibenzothiophene skeleton. 8. The light emitting device according to claim 7, further comprising another light emitting layer disposed in a stacked manner with the light emitting layer, and the another light emitting layer emits light in a color different from that emitted by the light emitting layer. Organic light emitting device. The organic light emitting device according to claim 17, which emits white light. A display device comprising a plurality of pixels, at least one of the plurality of pixels comprising the organic light emitting element according to claim 7 and a transistor connected to the organic light emitting element. It has an optical section having a plurality of lenses, an image sensor that receives light that has passed through the optical section, and a display section that displays an image captured by the image sensor,
A photoelectric conversion device, wherein the display section includes the organic light emitting element according to claim 7. An electronic device comprising: a display section having the organic light emitting element according to claim 7; a casing in which the display section is provided; and a communication section provided in the casing and communicating with the outside. . An illumination device comprising: a light source having the organic light emitting element according to claim 7; and a light diffusion section or an optical filter that transmits light emitted from the light source. A mobile object comprising: a lamp having the organic light emitting element according to claim 7; and a body provided with the lamp. An exposure light source for an electrophotographic image forming apparatus, comprising the organic light emitting element according to claim 7.

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